Automatic pneumatic liquid fuel atomizer for diesel engines



W. FELS AUTOMATIC PNEUMATIC LIQUID FUEL ATOMIZER FOR DIESEL ENGINES Filed April 16, 1954 INVENTOR. ax... 0

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Patented July 13, 1937 AUTOMATIC PNEUMATIC LIQUID- FUEL ATOMI'ZER FOR DIESEL ENGINES William Fels, Fairhope, Ala., assignor to F S K Manufacturing'Company Inc., Baldwin County, Ala., a corporation of Alabama Application April 16, 1934, Serial No. 720,800 6 Glaims. (ill. 299-1018) This invention relates to improvements in fuel and air mixing and atomizing devices and, particularly, to a device of this character for use in connection with the fuel feed for engines of the Diesel type.

Primarily, the invention contemplates the provision of an automatic fuel mixer and atomizer, with which the engine may be operated with greater economical efiicien'cy, regardless of speed of the engine or the load imposed thereon.

'Anotherobject is the provision of a fuel feed device of this character which is of simple but durable construction.

A still further object is the provision of a fuel feed device wherein the quantity of fuel and air supplied to the mixing chamber may be varied at will, independently of the speed of operation of the engine.

More specifically, the invention provides a fuel feed device wherein the fuel and air are supplied to a mixing chamber through separate passages, the flow of said fuel and air to the chamber being controlled by a valve yieldingly held closed, but

operable or movable to open position when a.

25 certain predetermined pressure is exceeded in one of said passages, usually the fuel passage.

With these and other objects in view, the invention consists in certain details of construction and combinations and arrangements of parts all 30 as will hereinafter; be more fully described and the novel features thereof particularly pointed out in. the appended claims.

In the accompanying drawing illustrating the preferred embodiment of the invention 5 Figure 1 is a sectional view on the line l5-l5 of Fi 2; Fig. 2 is a top plan view of the device;

Fig. 3 is a vertical sectional view on the line lG-IS of Fig- 2;

40 Described. generally, the device comprises a,

body l8 secured to the engine casting by a series of bolts 29, 30, 3!, 32, the bolts having nuts 33, 34, 35; 36, applied thereto in accordance with customary practice. v 5 In the interior of body l8, there is a mixing chamber 54 and communicating with said-chamber are the fuel and air passages, the fuel passage, in the present instance, being indicated at 41, and the air passage at 48. Each passage is 50 reduced in cross section as it approaches the mixing chamber, the fuel passage being reduced somewhat more than the air passage. The reduced portion 49 of the fuel passage is of lesscross' sectional area than the mixing chamber 55 so as to form a shoulder 52, while the cross section of the reduced portion 50 of the air passage is somewhat larger than-the mixing chamber so as to produce a shoulder 53. Leadingfrom the mixing chamber 54 is a passage 55 extending to the exterior of the body i8. The exterior sur- 5 face of said body is recessed as at 62 in order that a nozzle 2!, shouldered as at 22, may be seated therein. Said nozzle projects through an opening 23 in the engine casting 51, the inner end of the nozzle being exposed in the combus- 10 tion chamber 56. Gaskets 45, 46, may be used for securing an air-tight fit between the nozzle.

, and the associated parts of the structure.

Fuel feed pipe 31 is connected lntofuel passage 41 by means of externally screw threaded 15 connecting element 40 screwed into said passage. the pipe 3'! being secured in said connecting element 40 by the threaded nut 43. Likewise, air supply pipe 38 is connected to air passage 48' by threaded connecting element 4i and nut 44. The

inner end of connecting element 4| is recessed, by having the bore thereof tapered, as shown in Fig. l,- to provide a shoulder for a spring 21 of the spiral type. Said spring 21 is adapted to receive a shank of valve member 24 which is 25 composed of a conical member, as shown in Fig. 1, the cross section of said tapered or conical valve being such that it will simultaneously'close both the fuel and air passages by engaging the shoulders 53, 52, heretofore described.

Fuel is supplied through pipe 3'! under pressure by the use of a timed fuel pump (not shown). In. other words, until a predetermined pressure is placed upon the fuel in pipe 31, spring 21 will hold valve 24 closed but, when the engine is to be placed in operation, the fuel pump is actuated so as to build up the pressure of the fuel in pipe 31 to a point in excess of said predetermined pressure, whereupon valve 24 will be unseated and fuel and air both admitted to the mixing chamber 54. The air will also be under pressure and. with both air and fuel under pressure they will be violently mixed in the mixing chamber 54 from whence they will flow from the combustion chamber of the engine through passage 55 and nozzle 2i. This violent mixing of the liquid fuel with the compressed air in combination with the tearing up effect of a rapid expansion of the mixture, results in the condition of the fuel in highestvolatilefform which, properly distributed in the combustion chamber, assures complete rapid combustion.

With the presentconstruction, the action of valve 24 is automatic by reason of the fact that it is actuated by pressure of the fuel'created by 5 the timed fuel pump. This, of course, is entirely different from having the valve controlled directly by the load placed upon the engine. In other words, the quantity of fuel admitted can be governed or regulated absolutely independently of variations -in engine speed or the load imposed upon the' engine.

Thespecific design of the device is also very simple, in that the differences in the cross sectional areas of the fuel and air inlets and of the mixing chamber provide the necessary valve seats and a single valve may be used for controlling the two constituents of the fuel mixture. In the preferred construction, as shown, the-two passages, one for the fuel and the other for the air, are axially alined, thus facilitating the use of a single valve member. It will be understood that the cross sectional shape of the valve menuber 24 may be varied to conform to the cross section of the passages and chamber, a conical valve being used where the borings in the body l8 are circular.

What is claimed is:

1. In a fuel and air mixing and atomizing device, a body having a mixing chamber therein with fuel and air passages communicating with said chamber shoulders spaced longitudinally of said passages and forming concentrically arranged valve seats in said passages at opposite sides of said chamber, a valve controlling communication between said passages and chamber, and means for yieldingly holding said valve closed on said seats against a predetermined pressure in one of said passages, whereby excessive pressure in said passage will open said valve and establish communication between both passages site sides thereof, shoulders spaced axially of said passages and forming valve seats at said opposite sides of said chamber, a valve engaging both of said shoulders to close said passages, said valve being movable axially of said passages out of contact with said seats by pressure of fuel in the fuel passage, and means for yieldingly holding said valve closed.

3.1m a fuel and air mixing and atomizing device, a body having a mixingchamber therein with axially alined fuel and air passages extending from opposite sides thereof, the cross-sectional area of one of said passages being less than that of the chamber and the cross-sectional area of the other passage being greater than that of the chamber, whereby shoulders constituting valve seats are formed at opposite sides of said chamber, a tapered valve movable axially ofsaid passages, and means for yieldingly holding said valve in contact with both of said seats.

4. In a fuel and air mixing and atomizing device, a body having a mixing chamber therein and fuel and air passages communicating with said chamber at opposite sides thereof, and a valve extending through said chamber and normally closing both of said passages, said valve being movable by pressure of fuel in the fuel passage to open both of said passages.

5. In a fuel and air mixing and atomizing device, a body having a mixing chamber therein with fuel and'air passages merging into said chamber, said passages being in alinement with each other, and a slidable valve member nor-v mally extending into both of said passages and closing the same, said valve being movable to open said passages by pressure of .fuel in the fuel passage.

6. 111a fuel and air mixing and atomizing device, a body having a mixing chamber therein and fuel and air passages merging into said chamber at opposite sides thereof a valve seat for each passage, and an elongated valve normally engaging both of said seats, said valve being movable to open both of said passages by pressure of fuel in the fuel passage. 

